A controllable drive wheel for an industrial truck with two drive gears is known from the DE 41 10 792 C2. A miter gear with two miter wheel gears is arranged such that a respective output spindle drives the drive gears. The miter gear is driven by an electrical drive motor on a planetary gear that is arranged parallel or co-axial to the central axis of the device. Furthermore, a steer wheel motor is provided and is mounted outside the wheel gear case directly on the chassis of the industrial truck or on an additionally arranged head, plate torque proof to the chassis. With the operation of this steer wheel motor, this turns on a steer gear stage the wheel gear case or the gear carrier in its rotating assembly journal and thus also the wheel gear with both the wheel drives at the steering axle. The disadvantage of this steerable wheel drive is that the lateral arrangement of at least the steer drive motor makes the entire device less compact.
In addition, DE 199 04 552 A1 shows a wheel drive for an industrial truck for which an electrical traction motor and a gear driven by this are arranged co-axial to the longitudinal axis of the hub of the wheel of rotor. The traction motor is thereby designed as an electric motor with a disc-shaped rotor. Furthermore, the wheel drive exhibits electromotor steering with a steer motor and a steer gear, by which the steer motor is necessarily arranged perpendicular to the stage and is mounted by the turning of the rotor by the entire longitudinal axle of the wheel hub, traction motor and gear. The steer gear is a Wolfram-gear.
Although this wheel drive is very compact in the entire device, through the mentioned wheel hub drive as well as integration of the steer motor and the steer gear, its constructive formation, especially due to the cramped measure in the area of the wheel hub is comparatively complex and, therefore, costly. A further disadvantage is considered that the revealed combination of traction motor and gear, as well as steer motor and steer gear, develops a relatively large diameter size wheel drive.
Against this background, the task underlying the invention is to manage a constructively simple electro-motor steering and driving system for an industrial truck that exhibits a small diameter compared to known steering and driving systems and which could be manufactured at a comparatively cheaper cost with an acceptable design.